In a conventional automatic handgun, a trigger is provided with a related mechanism which controls and releases a spring-loaded firing pin. Mostly due to the automatic nature of this firearm, the trigger pull is extremely heavy and has a set poundage which is required by the firing mechanism spring. For certain applications, such as target shooting, it is desirable to use a very light trigger pull, being less than the conventional seven-pound pull and closer to a one or two-pound pull. Furthermore, it is often desired to adjust the trigger pull to a particular setting which may vary greatly between different persons shooting the firearm.
Prior art examples of firearms with selective trigger pull employ complicated mechanisms which are not adjustable and which allow for only two alternative trigger pull settings. A recent example is disclosed in the U.S. Pat. No. 4,005,540 to Robinson.